1. Field of Invention
The invention relates to discovering, using wireless communication, a service provided by a device prior to establishing a connection with the device.
2. Discussion of Related Art
Wireless communication technologies such as 802.11x and Bluetooth enable devices to communicate wirelessly over a relatively short range, e.g., less than 100 meters. To discover other wireless devices, a device broadcasts wireless messages and listens for wireless messages from other devices. If another device is discovered, a wireless connection may be established between the devices. Once a connection is established, devices may exchange various types of information. For example, devices may exchange information related to providing a service (e.g., printing, headset connectivity, PDA synchronization, etc.) provided by one of the devices.
A variety of services may be provided by communicating wirelessly between devices. As one example, a laptop computer may communicate wirelessly with a printer to print documents. Once a wireless connection is established between the computer and the printer, the computer may discover the print services provided by the printer. The computer may then take advantage of printing services offered by the printer via the wireless connection.
Previously developed IP-based methods of discovering services require a connection to be established with a device before services provided by a device can be discovered. For example, network discovery protocols such as SSDP (Simple Service Discovery Protocol), WS-Discovery (Web Services Discovery), and SLP (Service Location Protocol) require network layer connectivity (Layer 3 of the OSI model) to be established prior to the discovery of services on the network. Once connected, services provided by a device send broadcast or multicast messages over the IP network to advertise their services. Previously developed IP-based methods of service discovery did not provide a way of determining whether the device that provides the service was in the proximity of the device that required the service.